Dentures are conventionally made by insertion of acrylic or porcelain artificial teeth into a molded plastic dental plate base. The teeth are inserted into the dental plate when the dental plate is in a molten state, so that as the dental plate cools and/or cures, the artificial teeth become fixedly mounted in the dental plate. The dental plate material is conventionally made of a flesh-colored plastic so as to resemble natural gums, and the artificial teeth are conventionally made of an off-white plastic so as to resemble natural teeth.
Artificial teeth are subject to significant mastication forces. Over time, these forces tend to loosen artificial teeth from their attachment in the dental plate in which they are mounted. Eventually, artificial teeth may pop out of the dental plate. Such displacement can cause substantial embarrassment to the denture wearer, who is further inconvenienced by the cost and time required for denture repair.
To prevent such loosening, an adhesive is sometimes applied between the artificial teeth and the dental plate material in which the teeth are mounted. In addition, artificial teeth may be formed with a slightly enlarged mid-section which is positioned just below the natural "gum line" of the dental plate. When such artificial teeth are mounted in the dental plate, the dental plate extends slightly over the enlarged mid-section to form a "gum line" rim or flange which helps maintain the artificial teeth in the dental plate. Because, however, this "gum line" rim of dental plate material typically extends over the enlarged mid-section of artificial teeth only to 1/2 millimeter, the rim may not have sufficient strength to counteract the repeated mastication forces to which the artificial teeth are subject. Eventually, the "gum line" rim of dental plate material may break, allowing the artificial tooth over which it extended to become displaced from dental plate in which it is mounted.
In an attempt to further secure artificial teeth in dentures, cavities are sometimes formed in artificial teeth. Such cavities may extend from the base of an artificial teeth into the interior of the artificial tooth. When an artificial tooth is so constructed, during denture assembly molten denture plate material flows into the cavity formed in the artificial tooth, thereby extending a portion of the dental plate into the artificial tooth. While this construction does increase the surface area of contact between the denture plate and the artificial tooth, the artificial tooth may still exhibit a tendency to slip out of the denture plate after experiencing the repeated stress of mastication.
When artificial teeth fall out of a dental plate, the denture and loose artificial tooth must be repaired. Naturally, the repair process creates significant inconvenience to the denture wearer. If a "gum line" rim is broken, the repaired denture may appear flawed. Moreover, if the portion of the denture plate which extends into the core of an artificial tooth has been broken, the repaired denture may be unable to withstand mastication forces as well as the original denture.
It is against this background that the significant improvements and advancement of the present invention have taken place in the field of dentures.